Presence refers to a user's ability and/or willingness to participate in communications. Presence information, referred to as presence status or presence state, provides an indication of presence. Examples of general presence information are whether a mobile communication device is on or whether the mobile communication device is in communication with a wireless network (e.g., whether the mobile communication device is in coverage area).
Traditionally, presence information is managed by a presence server. When updating presence information, each mobile communication device which shares presence information with the presence server is periodically polled by the server to obtain its current presence status. Alternatively, changes in presence states may be pushed from the mobile communication devices to the presence server. Changes in presence status are then sent to each device in a group of mobile communication devices which share presence information (e.g., as determined by the respective device users). However, a presence server requires its own hardware, infrastructure, overhead and administration adding to the total cost of ownership. There are also privacy concerns with presence servers in regards to how access to presence information is controlled. Thus, there remains a need for improved presence systems.
Like reference numerals are used in the drawings to denote like elements and features.